CppEditor: Extract CanonicalSymbol

Change-Id: I42c55f844c4228725251df8c985bfc275925f2ff
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>

src/plugins/cppeditor/cppcanonicalsymbol.cpp

@@ -0,0 +1,138 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of Qt Creator.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+****************************************************************************/
+
+#include "cppcanonicalsymbol.h"
+
+#include "cppeditor.h"
+
+#include <cpptools/cpptoolsreuse.h>
+#include <cplusplus/ExpressionUnderCursor.h>
+
+#include <QTextCursor>
+
+using namespace CPlusPlus;
+
+namespace CppEditor {
+namespace Internal {
+
+CanonicalSymbol::CanonicalSymbol(CPPEditorWidget *editor,
+                                 const Document::Ptr &document,
+                                 const Snapshot &snapshot)
+    : m_editorWidget(editor),
+      m_document(document),
+      m_snapshot(snapshot)
+{
+    m_typeOfExpression.init(document, snapshot);
+    m_typeOfExpression.setExpandTemplates(true);
+}
+
+const LookupContext &CanonicalSymbol::context() const
+{
+    return m_typeOfExpression.context();
+}
+
+Scope *CanonicalSymbol::getScopeAndExpression(const QTextCursor &cursor, QString *code)
+{
+    if (!m_document)
+        return 0;
+
+    QTextCursor tc = cursor;
+    int line, column;
+    m_editorWidget->convertPosition(tc.position(), &line, &column);
+    ++column; // 1-based line and 1-based column
+
+    int pos = tc.position();
+    QTextDocument *textDocument = m_editorWidget->document();
+    if (!CppTools::isValidIdentifierChar(textDocument->characterAt(pos)))
+        if (!(pos > 0 && CppTools::isValidIdentifierChar(textDocument->characterAt(pos - 1))))
+            return 0;
+
+    while (CppTools::isValidIdentifierChar(textDocument->characterAt(pos)))
+        ++pos;
+    tc.setPosition(pos);
+
+    ExpressionUnderCursor expressionUnderCursor;
+    *code = expressionUnderCursor(tc);
+    return m_document->scopeAt(line, column);
+}
+
+Symbol *CanonicalSymbol::operator()(const QTextCursor &cursor)
+{
+    QString code;
+
+    if (Scope *scope = getScopeAndExpression(cursor, &code))
+        return operator()(scope, code);
+
+    return 0;
+}
+
+Symbol *CanonicalSymbol::operator()(Scope *scope, const QString &code)
+{
+    return canonicalSymbol(scope, code, m_typeOfExpression);
+}
+
+Symbol *CanonicalSymbol::canonicalSymbol(Scope *scope, const QString &code,
+                                         TypeOfExpression &typeOfExpression)
+{
+    const QList<LookupItem> results =
+            typeOfExpression(code.toUtf8(), scope, TypeOfExpression::Preprocess);
+
+    for (int i = results.size() - 1; i != -1; --i) {
+        const LookupItem &r = results.at(i);
+        Symbol *decl = r.declaration();
+
+        if (!(decl && decl->enclosingScope()))
+            break;
+
+        if (Class *classScope = r.declaration()->enclosingScope()->asClass()) {
+            const Identifier *declId = decl->identifier();
+            const Identifier *classId = classScope->identifier();
+
+            if (classId && classId->match(declId))
+                continue; // skip it, it's a ctor or a dtor.
+
+            if (Function *funTy = r.declaration()->type()->asFunctionType()) {
+                if (funTy->isVirtual())
+                    return r.declaration();
+            }
+        }
+    }
+
+    for (int i = 0; i < results.size(); ++i) {
+        const LookupItem &r = results.at(i);
+
+        if (r.declaration())
+            return r.declaration();
+    }
+
+    return 0;
+}
+
+} // namespace Internal
+} // namespace CppEditor